The present invention relates to apparatus useful to provide benefits to respiratory gases. More particularly, the invention relates to apparatus for heating and humidifying respiratory gases, and preferably in providing additional treatments to patients.
During surgery and other medical procedures, a patient is frequently connected to an anesthesia machine or ventilator to provide respiratory gases to the patient. The respiratory gases passed to the patient are advantageously heated and humidified so that the gases entering the patient are of a suitable temperature and humidity so as not to adversely impact the patient. Heat and moisture exchangers (HMEs) are often used to provide heat and humidity to the respiratory gases entering the patient. Typically, these HMEs are located so that respiratory gases from the patient pass through a tracheal tube into the HME, often a fibrous or other gas permeable material, which accumulates or collects heat and moisture from the exhaled gases. During the inhaling of respiratory gases, for example, from an anesthesia machine, the HME provides both heat and moisture to these respiratory gases prior to the gases entering the patient. Over a period of time, the HME is effective to maintain a certain level of temperature and humidity in the respiratory gases entering the patient.
Such HMEs do, however, have certain drawbacks. Thus, HME unites currently commercially available have configurations and structures which can cause clinician anxiety and patient trauma, for example, when the patient using the HME is to receive an additional treatment, for example, a nebulizer treatment or like treatments.
To illustrate, using currently commercially available HME units and patient manifolds, when an additional treatment is to be provided to the patient, the HME unit and/or patient manifold is disconnected from the patient and the device for providing the additional treatment is connected to the patient to provide the additional treatment. During the interim, that is between the disconnection of the HME unit/patent manifold and the connection of the additional treatment device, the patient is depressurized and without external mechanical breathing support. Any failure to quickly connect the additional treatment device can result in substantial trauma to the patient, particularly when the patient is a child or infant or otherwise in critical cardio-pulmonary condition. Also, the need for the clinician to rapidly and effectively connect the additional treatment device does create a high level of clinician anxiety which can result in clinician ineffectiveness, ultimately resulting in increased risk of harm to the patient. Experience has shown, even with quick reconnection, conscious patients experience anxiety induced higher pulse rates and blood pressure.
Wikefeldt U.S. Pat. No. 5,546,930 discloses a device including a bypass line which bypasses respiratory gases from a ventilator or anesthesia machine through a nebulizer into the tracheal tube of the patient. However, this patent discloses that the bypass line withdraws respiratory gases downstream of the in line filter which can result in less effective bypass of the respiratory gases. Also, the patent still requires that plugs be physically removed to allow flow in the bypass line. Such plug removal from the bypass line results in a depressurization of the unit and a resulting increase in clinician anxiety/patient trauma, as discussed above.
It would be advantageous to provide apparatus by which respiratory gases can be effectively and reliably heated and humidified and which can be effectively used in providing additional treatments to the patient so that the comfort and safety of the patient is enhanced and the stress on the clinician is reduced.